A Trip to the Nord Stream Blast Sites
Sonar Maps, Film and Models
This post is intended as a supplement to media reports about our small survey trip to the Nord Stream blast sites May 22-25 2023. The purpose of the trip was to create some more transparency to a subject that’s been, and still is, shrouded in secrecy. Therefore I wish to make available to everyone all the materials we were able to retrieve during our visit to the explosion sites. Maybe other researchers can find new things in the underwater video or the sonar maps that we captured. I hope also that future expeditions can use our material to focus their effort on finding new pieces in the puzzle.
Our Route and Naming of Sites
We started at 5PM on Monday May 22 and returned at noon May 25. The boat made only 6 knots, so there was a lot of transit time. We spent most of May 23 on the Southern site. And worked from the morning to 1AM on the northern site. Each sonar survey was about 4 hours, and then there was filming for 1-2 hours. Wind and waves picked up in the late evening of May 24 making sonar work difficult. We had prioritize and skipped the underwater filming of the Nord Stream 1 sites.
The four different explosion sites on the map above are named NSXYZ,
where,
X = 1 for “Nord Stream 1”, and X = 2 for “Nord Stream 2”
Y = A for “String A” and Y = B for “String B” (each line has two pipes called “strings”)
Z = D for “Denmark” and Z = S for “Sweden”. This letter depicts the economic zone of the site.
NS2AD At 2:03:20 LT the 26:th of September 2022. From the seismic signature, this was a single explosion, or possibly two simultaneous explosions. This occurred on “String A” of NS2, the line closest to Bornholm. String B is undamaged at this site, and everywhere else too. The B-line is currently pressurized to 50 bars. String A was pressurized to 104 Bars at the time of the explosion according to the NS2 corporation and Reuters.
NS1AS At 19:03:50 LT the same day an explosion was registered at this site, and 7 seconds later there was a second explosion of similar magnitude on the same site 200 meters away. This explosion (or pair of explosions) has only damaged the A-line of Nord Stream 1. The B-line is intact at this site. The A-line was pressurized to 164 bars at the time of the explosions. The distance between the open ends of the pipeline is 249 meters and there are 5 distinct craters.
NS1BD At 15 seconds after the first NS1AS explosion, there was an explosion which the seismologists have attributed to this site in preliminary analysis. The signal is too blurred at this stage to say if there was a single or multiple explosive events. Only the B line of Nord Stream 1 was affected here and the distance between the open ends is 284 meters. The pattern of 5 craters is almost identical to the pattern found at NS1AS.
NS2AS This explosion is not registered seismically in a way where the relative location to NS1AS and NS1AD can be determined, but I assume that it happened in the same noisy short time period as it otherwise would have been discovered with its own signature. The pipeline is not significantly displaced here, but we have documented the primary damage from an explosion. The bomb was placed on a seam and the concrete was blown away on the side of the seam in a two meter wide area. Our footage from this site is the most valuable as its analysis will likely reveal the placement, size and magnitude of the bomb(s) . As the explosion occurred on the same A-line of Nord Stream 2 that had already been ruptured 17 hours earlier, there was no significant overpressure and thus no thrust forces that could throw the pipe around as on the other sites. It’s clear from the size of the hole though, that IF the pipe had been pressurized, it would have looked similar to the other sites.
The Materials
This chapter is organized into one section for each explosion site, and then there are subsections for sonar maps, film and models. The sonar mapping was performed in two phases by Patrik Juhlin with the assistance of Rico Friis. The objective of the first phase was to get a depth map of the areas and it was performed with a regular echo sounder shooting a narrow beam towards the bottom while the boat passed back and fourth over the sites. The result are “point clouds” which are provided below as CSV files with three columns (Latitude, Longitude, Depth). This data has been Delaunay-triangulated by my friend Tommy Bohlin to the CAD format. STL. Tommy used that to do 3D prints of the topography which I used in the interviews with Die Zeit and ARD. The STL files are also provided here in downloadable format. At the time of this writing I have not been able to use the original data points for interpolation and some information is lost in the interpolation performed by DeepVision’s proprietary software.
The second phase of sonar mapping used a towable “side scan sonar” which produces something resembling a photographic image of the bottom.
Our side scan sonar was embedded in a so called “fish” which was towed about 150 meters behind the boat and about 6-8 meters above the bottom. The Baltic sea is stratified with fresh water on top and denser saline bottom water that has a higher speed of sound. The difference in sound speed causes the sonar pulses to bend and blur the images unless the transponder is submerged into the bottom layer. Our side scan images provided here are revealing but not without artifacts. The transponder sends sonar pulses as the sides as it travels over the bottom and records the time and magnitude of echoes. Hard objects like the pipeline are white in color and the soft mud is brownish. You can see the “seams” of the pipeline in a darker color as they are covered by soft polyurethane foam. The computer software that turns the signals into an image works best when the bottom is flat. When there are deep craters below the “fish” the side of the crater can be at the same distance as the bottom and the pipeline therefore can appear to bend to the side although it actually bends down vertically. I’ve been working together with image analyst Michael Kobs to combine scans to the left and the right of an area to overcome this artifact and compute the correct geometry. Another artifact seen in our images are due to the surface waves which cause the boat speed to oscillate a little and the fish to move up and down. This causes straight objects like the pipeline to sometimes meander. Models with geometry corrections are linked in the model sections. This is work in progress. Models will improve over time, and hopefully new expeditions with different equipment, like multi-beam sonars and photometric ROV mapping will eventually sort out remaining question marks about the crime scene.
Finally there is some underwater footage taken on the two Nord Stream 2 sites, and again some geometric models created by Michael Kobs by combining video-frames from different angles.
NS2AD
Sonar Depth Point Cloud in CSV
(kudos to Michael Kobs for assembling lots of small screenshots from the “free viewer” to the above JPEGs which give an overview of both pipeline strings)
Models:
Above is a preliminary layout of the scene by Michael Kobs. I agree with this rendition in terms of the general position of the pipe. There is very little displacement to the sides, and it is broken in at least two places. We are still debating the amount of pipe that seems to be missing in the “gap” between the northern end that’s flying at 73 meters depth and the southern end that’s resting on rock at 77.5 meters depth. The gap is 7 meters and I believe it’s displaced 4 meters because its projection on the horizontal plane is simply that much shorter when its bent up and down 10 meters. Three meters are still unexplained by this, and if you look at the sonar scans linked above you can see something looking like a seam about 9 meters from the end. Furthermore, footage by Trond Larsen from BlueEye Robotics on June 13 reveals a cut that doesn’t look like a seam on the northern end. I don’t think we can exclude that a bomb exploded here and that the primary damage of that explosion was removed by investigators along with 3 meters of pipe.
Film of Trench under Northern End
Trond Larsen from Blue Eye Robotics acquired better footage of both ends published here
NS1BD
Sonar Depth Point Cloud in CSV
We did not send down our ROV to film this site as we had to do three sites this day and wanted to focus on NS2AS.
NS2AS
We did not create a point cloud or an STL mesh for this site since it’s almost completely flat. However, the brilliant Michael Kobs was able to produce a this model of the small crater geometry by simulating the shadow from the sonar scan by artificial lighting:
Film Please note in this footage that the damage is on the southern side of the pipeline, but the compass of the ROV is almost 180 degrees wrong. I was fooled by this when filming and kept looking for a hole on the wrong side since I had seen the crater on the sonar before diving. I think the compass failure might be systematic in the area. Trond Larsen had similar issues on the NS1AS site, and BBC ended up turning their map upside down and because of it. Since I was fooled myself, I think it’s likely the saboteurs were also fooled and placed this bomb on the wrong string.
NS1AS
Note that the standing pipe documented by BBC is actually situated very near the original position of the pipe. The compass error caused BBC to turn the map upside down and falsely conclude that the vertical pipe had flown 150 meters away.
Eight Bombs or just four?
The Intercept article mentioned that my son Aron had helped solve “Euler’s equations in the geometry of the pipeline”. Here’s comes little background to that, why it matters, and a link to a paper with his calculations.
I always assumed that all sites were rigged in a similar fashion. I admit this is an assumption, I have no hard evidence, but there is also no evidence the bombs were different. I think it makes little sense to use different bombs in the different locations, especially if you are a small team and trained to finish a job under time pressure. You make your calculations and then you apply the same dose of the same medicine to all four strings of the pipeline. I’ll stick to this hard assumption until proven wrong.
When Seymour Hersh said there was a total of eight bombs, two for each pipeline I thought that was very interesting because it meant there must have been unexploded bombs somewhere, and the idea that someone came to pick them up after the blasts was intriguing. If you assume that there were two bombs for each of the four lines, there would either be two unexploded bombs on the NS2B line, or if the NS2AS bomb was a mistake that would have had an unexploded sister bomb close to it. Andreas Köhler’s abstract identifying two separate seismic events in the NS1AS area, just 200 meters from each other, implied that there had to be two bombs there. The operator of the pipeline made a press release after their first survey which was widely interpreted by the press as two bombs at the same site. In the early film footage from the NS1SQ site you could also see two bubble plumes, and the Danish authorities put two hazard markers, roughly 250 meters apart on the sea chart over the NS1BD site. There were lots of reasons to assume that each of the four lines was rigged with double bombs. Perhaps the perpetrators had planned for a bit of redundancy to make sure their mission was successful.
But there is still no hard evidence of any line being rigged with two bombs. The two “craters” in the Gazprom press-release turned out to be trenches created by the stream following the rising gas bubbles. This is a known phenomenon often used by divers to clean surfaces from loose materials underwater. Actually there were five discernible holes along the open 250 meters of missing pipeline, and the Danish NS1BD site looks very similar. How would two bombs create five craters? Five is an odd number, so a single bomb causing a chain reaction sounds much more plausible.
For the highly pressurized NS1 pipeline, I have been told it was 164 bars, I now believe there was just on under the pipeline in the position of the central crater in the graphic above. The unleashed pressurized gas lifted that spot causing new ruptures by the intermediate craters, resulting in new lift forces and final ruptures by open ends which are now 249 and 285 meters apart in the Swedish and Danish NS1 sites respectively.
The single bomb theory isn’t proven by the above logic, but it’s the simplest assumption that fits with observation so it should be the working hypothesis. It’s an attractive hypothesis because it means we now know the location (at least approximately) of all four bombs. Also, if there were just four bombs, the idea that two of the four bombs were placed on the same pipeline on purpose falls apart completely. You don’t make an extra trip to a new location with lots of ship traffic, or a location with already rigged bombs for that matter, if your only objective is to be little closer to 100% sure your mission to blow up exactly three of the strings is successful. You don’t expose yourself to such tremendous risk if your upside is that small.
So what about the seismologists reports of double blasts in close proximity?
The seismologists don’t like it when I say this, but I know they thought in the beginning of June that both pipes had been blown up at NS1S because they assumed a pipeline had exploded it can’t explode again. Although that’s true for a balloon or any small pressure vessel, I wasn’t sure it was true for the pipeline. Maybe if a punctured pipeline broke in a new place a few seconds later it would create a new bubble which oscillates to produce a new seismic signal. If that was true, a single bomb could have created both of the first two seismic events around 19:04 on September 26, and there would be no seismic evidence of double bombs. This is was Aron was able to confirm by solving Euler's equations for the situation that a very long pressurized gas filled tube suddenly opens up. The solution was easier to understand than I thought. After the rupture, a (de)-pressure wave travels with the speed of sound towards Russia and Germany. But behind that pressure wave the conditions are almost constant. If it wasn’t for friction against the walls of the pipeline, gas would keep flowing out at 18 tons per second until the pressure wave returned. Friction soon becomes significant, but after 7 seconds, if the pipe is whipped around and breaks 200 meters upstream, a new bubble is filled in the water at similar speed to the first bubble.
The initial mass flow of 18 tons per second by the way, is 40 times higher than the mass flow at the time when the first photographs were taken of the “bubbling sea”, That bubbling the first minutes would have been quite a sight.
The big Mistake
All large media articles about the expedition have quoted me saying that the divers who placed the bombs were likely misled by their magnetic compasses and ended up placing two of the four bombs on the same pipeline. This saved the B-string of Nord Stream two from being destroyed. What’s my evidence of this?
My first hint was that I was fooled my my own compass and was arguing with captain Patrik Juhlin for two days after the expedition believing that the rupture on the NS2AS site was to the North of the pipeline. He was right and I was wrong. The GPS-compass calibrated geo-tiff images from the side-scan sonar are solid evidence.
So how did I get this wrong? My drone, a Chasing M2 hobby drone, has a built in digital compass that measures the earth’s magnetic field along 3 axes. You have to go through a calibration procedure before each mission:
Above is a picture of me calibrating the compass by watching an instruction film on the iPad and performing the suggested movements. It has to be wiggled around all 3 axes. But I wasn’t content with that. I also placed the drone above the cockpit where Patrik could report the boats true differential GPS heading through an open window. The readings were roughly the same.
Then I made a final check by driving the drone along the surface. It was around 6PM and the sun was in the west. The compass seemed right. If you watch THE FULL MOVIE this is also documented around 12:40 (the movie is an hour and a half and 13 Gb to download. It’s a rough cut. Mistakes and bloopers included)
The camera was also on when I returned to the surface after the mission, and careful analysis of that footage and comparison to the sun’s position shows that on the surface, the compass was OK.
But still, in the water when looking straight into the hole on the south side the compass in the lower left shows 146 degrees.
But I’m not the only one who experienced this issue. BBC posted an upside down map of the neighboring NS1AS area.
I reviewed all footage that was published from Trond’s expeditions from his two expeditions and his compass reversal was as consistent as mine. I would like to encourage BBC to publish all of his footage from their trip since I know Trond also filmed a pipe end that now lies in a North-South direction. The image above is form the western open end of the V-shaped segment in NS1AS. He also filmed the opposite end of the V-shape.
My conclusion is therefore that the saboteur divers were misled by their compasses and placed a bomb on the A-string that was intended for the B-string. This doesn’t mean that this bomb was placed last. It could have been that the saboteurs had to abandon their mission in the northern area before they had finished the job and placed the final bomb. But just like the BBC, they left the area believing they had visited the southern B-string of the pipeline. This misconception led them to rig the same pipeline again in the southern site, where all available footage shows correctly working compasses. That’s what I think anyway.
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Is the belief that the pressure in the Nordstream 1 pipelines was 165 bar at the time of the explosions based upon confirmation from the pipeline operator or some other reliable source ? Or is it based upon predicted values obtained from project documentation prepared prior to the explosions ?
The settle out pressure if the pipeline had been operating at full capacity was calculated to be 165 bar because the inlet pressure would be 220 bar and outlet 105 bar (this can be obtained from Nordstream project documentation). However, for 3 weeks prior to the explosions the pipeline was operating at 20% capacity which implies that the inlet pressure would have been significantly less than 220 bar; it's been reported that the outlet pressure immediately prior to the explosions was 105 bar so the corresponding settle out pressure would be a lot less than 165 bar.
NS1 pipelines pressure would be expected to be higher than NS2 pipelines at the time of the explosions but maybe not to the degree suggested ie 105/165 bar.
Although ther is not too much hope, it may be recommended to do some trace sampling on the bottom of the craters with special collectors. If any traces remain thes can be collected in the end.